Researchers have found that a particular pattern of microbes in the digestive tracts of
one-month-old infants is linked to a three-fold
higher risk of developing allergic reactions by age two and asthma by age four
have linked the risk of developing allergies and asthma during childhood
to the microbes in the baby's gut during infancy.
who developed allergy or asthma in childhood had a particular pattern of
microbes in their digestive tract.
if the microbial content of the intestines is altered, it may be possible
to reduce the risk of allergy or asthma later in life.
. The research was published in the Nature Medicine.
is a chronic condition that
causes inflammation and narrowing of the bronchial tubes, the passageways that
allow air to enter and leave the lungs. In people with asthma, an attack may be triggered following exposure
to any substance to which they are sensitive or to a situation that changes
their regular breathing patterns.
‘The type of bacteria and fungi in the gut of new-borns can predict the development of allergy and asthma later in life.’
symptoms of asthma include shortness of breath
, cough, chest tightness, wheezing and chest pain, especially
in younger children. Childhood asthma
reduces quality of life by
interfering with school, play and other activities, and sleep.
In their study, researchers
collected stool samples from diapers of one-month old infants and stored them
on ice. They conducted repeated follow-ups during the first
year of life, and then checked the infants for allergies at the age of two and for asthma around their fourth birthdays.
The stool samples were recently
analysed to check for the presence of microbiome features.
researchers found that in the stool samples of 11 out of the 130 infants
included in the study, key types of gut bacteria like Bifidobacterium, Akkermansia and Faecalibacterium
were low in levels while certain
resident fungal species like Candida and Rhodotorula were relatively high. This particular pattern of
microbes in the gut of infants was linked to a three-fold
higher risk of developing allergic reactions by age two and asthma by age four.
researchers also examined the stool samples for the metabolic by-products of
microbes and discovered that neonates who had healthy gut microbes produced fat
molecules that normally reduce inflammation and nourish the immune cells called
T-regulatory cells, which determine the overall health of the immune system
lipids were absent in the guts of at-risk babies. On the other hand, they had
different fats, including one associated with asthma in adults, called 12, 13
This fat molecule could reduce the number of T-regulatory cells that keep the
immune system in check and eventually to chronic asthmatic
inflammation of the lungs
Co-senior author Susan Lynch, PhD,
a UCSF associate professor of medicine, says that the discovery
represents an opportunity to develop new treatments that could stave off
allergies and asthma before they become established.
"If we are to prevent disease
development, we need to intervene early," Lynch said. "Currently,
children are typically six or seven years old when they are diagnosed with
asthma, which has no cure and has to be managed through medication. But if the
genesis of the disease is visible as a disruption of gut microbiota in the very
earliest stages of postnatal life, it raises an exciting question: could we
reengineer the community of microbes in at-risk infants to prevent allergic
asthma from developing?"
"We have been working for over
a decade, trying to figure out why some children get asthma and allergies and
some don't," said co-senior author Christine Cole Johnson, PhD, MPH, who
is chair of public health sciences in the Henry Ford Health System. "It
seems that the microbial communities within the body could be the keystone to
understanding this and a number of different immune diseases."
"Asthma has doubled in
prevalence in modern "westernized" societies about every 20 years for
the past 60 or 70 years, so an effective strategy for prevention is becoming an
urgent need for public health," added Homer Boushey, MD, a professor of
medicine at UCSF, and member of the research team. "By focusing on the
differences in microbial functions -- in their metabolic products and their
effects on immune function -- this kind of study helps define the pathway we'll
need to follow to prevent this disease," he added.
"Humans have co-evolved with
microbes and as a result we rely on their genomes for certain critical functions.
We believe this is particularly true during the earliest stages of human
development," Lynch said. "But lifestyles have changed dramatically
over the past several decades: We've significantly reduced our exposure to
these environmental microbes our bodies rely on. Having a dog track the
external environment into the home may be just one way to improve the breadth
of microbes babies are exposed to in very early life."
The researchers hope these findings will spur development of tests to detect signs of an
unhealthy gut microbiome in infants and to implement early-life interventions
to shift microbial ecosystems towards a healthier state and thereby prevent
childhood allergies and asthma.
Management of Childhood
- Early identification of symptoms of allergies and asthma
by consulting allergist.
- Improving quality of life by keeping symptoms under
control through medication.
- Monitoring lung functions
- Avoid situations or substances that trigger attacks of
- Provide information on healthy eating, exercise,
avoidance of tobacco smoke, maintaining healthy weight and immunization.
- Fujimura KE et al. Neonatal gut microbiota associates with childhood multisensitized atopy and T cell differentiation. Nature Medicine (2016) doi:10.1038/nm.4176
- Overview - Asthma - (http://acaai.org/asthma/about)
- Childhood Asthma - (http://www.mayoclinic.org/diseases-conditions/childhood-asthma/home/ovc-20193095)
- Global burden of asthma among children. - (http://www.ncbi.nlm.nih.gov/pubmed/25299857)
- Asthma Surveillance Data - (http://www.cdc.gov/asthma/asthmadata.htm)
- Managing asthma in children - (http://www.asthmahandbook.org.au/management/children)